Gestation The state of being pregnant; the period from conception to birth. Find out more about otters in the different Asian countries. They hunt food by using their vibrissae to detect movements of prey in the water. The threat to small-clawed otter is prominent in its western range so much so that since last 60 years its range has shrunk considerably moving west to east from Himachal Pradesh to Assam. Behavioral signs at the onset of oestrus may include increased rubbing and marking. They are seriously threatened by rapid habitat destruction, hunting and pollution. Action plan for Asian otters, In Otters, an action plans for their conservation Eds. It inhabits freshwater wetland systems such as swamps, meandering rivers, mangroves and tidal pools as well as irrigated rice fields.